Shantae: From Half-Genie Hero to Half-Genie Zero:
Chance: 0.001%: Yeah, I think she's even less likely than Rex, and maybe even Shrek and Goku. Let's go over all of the evidence against her:
1: (The obvious) She's a spirit, which does deconfirm her.
2: WF talked about wanting her in as one of the DLC fighters, implying that she wasn't already chosen for DLC, since they'd need to be under an NDA, which was the only thing Shantae had going for her for the base game.
3: Considering how she keeps appearing as a spirit in the promotional content, it looks like she's the Waluigi of Spirits, so no promotion for her anytime soon.
4: There are many more likely indie reps. Sans, Travis, Steve (who's pretty much already confirmed) and even Shovel Knight are way more well-known, and more important to Nintendo (financially). With even one of these characters in the game, Nintendo would see no reason to add a second indie rep, not only for that game/DLC, but probably the next one, too.
5: Nintendo ignoring the fans moreso than usual: The only Fan-Favorites we've gotten were Inkling, Ridley and King K. Rool. All three of these fighters were either financial assets to Nintendo (Inkling) or the tip-top of the fighter ballot (Ridley and K. Rool). Everyone who wasn't those 3 was shafted for an Assist Trophy or a Sticker. Top contenders like Isaac, Waluigi, Skull Kid, Krystal, Lyn, Bomberman, Spring Man, Rex, and even Shovel Knight were written off as unworthy, and Shantae was so much of an afterthought that all they gave her was a sticker. So with so little for the fans, the DLC is not likely to get anyone for the fans. Even if there is one or two characters, they're probably not going to pick her.
6: She's unpopular. How many of you have heard of her before Smash? Not many. Enough said.
NEW: 7: People Hate her. Steve's been beating her on fan polls left and right, and only one or two people here (including me) have given her anything higher than a 20% on want score.
In the end, Shantae's place in Smash looks like it is and always will be a PNG file that wasn't even made for this game.
Want: 999% (If that's not allowed, then 100%.): And. It. Sucks. She, unlike the other indie competitors I mentioned, would represent the smaller side of indie games well. In addition to that, she has more moveset potential (thanks to her transformations, magic and pirate gear), and more personality (all her game's dialogue is like something out of KIU) than any of the other indie competitors. That and it would have just been the perfect rags-to-riches story with a Smash Bros Fan's work getting enough support to actually be in Smash.
I really consider her down for the count. and the next one. and the one after that. and maybe even the one after that. and you get the idea. Basically, Shantae's a lost cause, and anyone who's supporting her should just come to terms with her being a PNG file and move on.
Nomination: No Fan Favorites x5